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Yugang Reactor Inconsistency

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Hey all,

My DIY Yugang reactor seems to produce an inconsistent pH drop despite operating in "overflow" mode. Some days my drop checker is very green, and then there is a streak of days where it is quite yellow. I'd like to get this ironed out before I buy any fish so I don't gas them.

So far, I've explored the following causes for inconsistent day-to-day drops but none have consisently reproduced the issue.
1. Water Level & Surface Agitation --> Water level relative to filter outlet causes more or less surface agitation, and therefore different pH drops
2. Skimmer Operation --> whether or not filter inlet skimmer is operating properly that day
3. Bubble counter --> whether or not the bubble counter has run dry
4. Injection rate --> even in overflow mode, it can be tuned to purge more or less frequently depending on bubbles per second. In theory, this shouldn't change anything but seems to have at least some impact. I've done my best to completely purge the reactor of any air that gets trapped from water changes/filter cleaning so that it's pure CO2.

Anything I'm missing here that I should look at for potential causes?

After doing some more detailed math using CAD, my reactor is a little over-sized for this tank (approximately 1:20 reactor to tank surface area ratio). The reactor is 2" x 8" Clear Schedule 40 PVC pipe. While this explains why I sometimes get too large of a drop, it still doesn't explain why it's a bit inconsistent day to day.

@Naturescapes_Rocco @Yugang Would you all have any feedback on this?



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Some days my drop checker is very green, and then there is a streak of days where it is quite yellow

For your sanity's sake I would really recommend picking up a Hanna CO2 test kit, and find out exactly what those ppm values are 👍

 
For your sanity's sake I would really recommend picking up a Hanna CO2 test kit, and find out exactly what those values are 👍

I've got both an Apera pH60 and a Hannah CO2 kit, and I find the CO2 kit very difficult to read consistently. Trying to dial it in using both methods though.
 
I found that with a spray bar, if I am overflowing too much co2 it tends to build up in the spray bar and in essence create a second horizontal reactor causing higher output.
 
An easy way to smooth things out is to start injecting much earlier. If your lights come on, try starting CO2 at 4 or 5am, or even earlier, to help get things dialed in. If your DC is still green after 5 hours of injection, your setup is not good.
 

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